Like a creamless gratin, this potato casserole gets its flavor and richness from caramelized onions and chicken (or turkey) stock. For a sliceable texture, bake the casserole ahead of time and let it cool completely (during which time the gelatin in the stock and the starch in the potatoes will set), then reheat before serving.
Total time: About 3 hours
- 6 tablespoons unsalted butter, plus more at room temperature for the baking dish
- 2 large yellow onions, halved and very thinly sliced
- Kosher salt and freshly ground black pepper
- 1 garlic clove, halved
- 3 pounds fingerling potatoes, scrubbed
- 3 fresh thyme sprigs
- 4 cups chicken or turkey stock, preferably homemade
- Heat 3 tablespoons butter in a medium nonstick skillet over medium-high. When the butter is melted and foamy, add the onion and cook, stirring occasionally, until the onions are soft and translucent, 8 to 10 minutes. Reduce the heat to medium and continue to cook, stirring often, until the onions are golden brown, adding a splash of water to the skillet as needed if the bottom is getting brown, 25 to 30 minutes longer. Season the onion with salt and pepper, and scrape into a medium bowl. Set the bowl aside and reserve the skillet.
- Arrange an oven rack in the center position and heat the oven to 400 degrees. Rub the bottom and sides of a 3-quart baking dish with the cut sides of the garlic clove, then generously coat with room-temperature butter. Set the baking dish aside.
- Using a mandoline or a knife and a cutting board, slice about a third of the potatoes into 1/8-inch-thick rounds. Working quickly so the potatoes don’t brown, heat 1 tablespoon butter in the reserved skillet over medium-high, then add the sliced potatoes and 1 thyme sprig; toss until the potato slices are coated in the butter. Season lightly with salt and pepper, then continue to cook, tossing occasionally, until the potatoes are browned in spots and just starting to turn translucent and lose some of their crunchy texture, about 5 minutes. Scrape the potato mixture into a separate large bowl.
- Working in two batches, slice the remaining potatoes and cook with the remaining butter and thyme in the skillet just as you did the first batch. Transfer all the potatoes to the same bowl as the first batch and let cool for a few minutes (reserve the skillet).
- Scatter about a third of the potato slices in an even layer on the bottom of the prepared baking dish, then scatter about half the onions over top. (You can pluck out and discard the thyme sprigs if you like, or, if you don’t mind picking them out later, you can leave them in.) Scatter half of the remaining potatoes in the baking dish, then top with the remaining onions. Layer the remaining potatoes over top in an even layer, shingling them or arranging in a rosette, or you can leave them haphazard.
- Add the stock to the reserved skillet and bring to a simmer over medium-high heat. If using homemade stock, give it a taste and add salt as needed to make sure it is well seasoned (store-bought stock is usually already pretty salty). Remove the skillet from the heat and gently pour the stock into the baking dish just until it barely covers the potato slices. If you have any stock leftover, reserve it for moistening the potatoes as needed while they bake.
- Transfer the baking dish to the oven and bake uncovered until the potatoes are tender and golden across the surface and the stock is bubbling, reduced and has been mostly absorbed by the potatoes, 1 hour, 20 minutes to 1 hour, 40 minutes. If the surface of the potatoes seems to be drying out or if the potatoes absorb all the stock during baking, drizzle some of the reserved stock over top to moisten them. (If you don’t have any more stock, you can use water.)
- Remove the potatoes from the oven and let them cool completely at room temperature (turn off the oven). As it cools, the mixture will set and absorb the stock, but if you are using store-bought stock, it will stay a bit brothy. The potatoes can sit uncovered at room temperature for several hours.
- About an hour before serving, heat the oven to 350 degrees. Transfer the baking dish to the oven and bake uncovered until the potatoes are heated through, 20 to 25 minutes. Serve warm.
Do ahead: The pommes boulangère can be assembled and submerged in stock up to 24 hours ahead. Cover the baking dish and refrigerate, then let it come up to room temperature before baking. Note that it will take longer to bake since the stock will be room temperature rather than warm.
Duchess-Style Twice-Baked Potatoes
Unlike American-style twice-baked potatoes, which are laden with cheese and sour cream, these potatoes, inspired by the French dish pommes duchesse, get their richness primarily from egg yolks. While you can scoop the filling back into the skins with a spoon, piping it with a star-tipped pastry bag makes the potatoes especially fancy.
Total time: About 2 hours
- 6 medium russet potatoes (about 3 pounds), scrubbed
- ¾ cup whole milk
- ½ cup unsalted butter
- 1/8 teaspoon ground nutmeg
- Kosher salt and freshly ground black pepper
- 4 large egg yolks, at room temperature
- Sweet paprika, for topping
- Arrange an oven rack in the center position and heat the oven to 425 degrees. Bake the potatoes directly on the oven rack until the flesh is soft and tender and the skins are crispy, 60-75 minutes. Remove the potatoes from the oven and let them sit at room temperature just until they are cool enough to handle (they should still be hot). Leave the oven on.
- Meanwhile, combine the milk and butter in a large saucepan and bring to a simmer over medium-high heat, then reduce the heat to the lowest setting just to keep the mixture warm. (It should not be bubbling.)
- Cut 2 of the still-hot potatoes in half lengthwise and carefully scoop the flesh into a food mill, ricer or drum sieve, taking care to keep the skins intact. Set the skins aside, then mill, rice or press the flesh into the saucepan. Repeat with the remaining potatoes in 2 more batches, reserving 8 skins total (you can snack on or discard the 4 other skins).
- Add the nutmeg to the saucepan and generously season the potato mixture with salt and pepper. Remove the saucepan from the heat and gently fold until the mixture is smooth, then taste and adjust the seasoning. Gently stir in the egg yolks until combined. Set the saucepan aside and let the potato mixture cool completely to room temperature, stirring occasionally.
- Place the 8 potato skins on a rimmed baking sheet, spacing them evenly. For a fancy (but optional) look, scrape the potato mixture into a pastry bag fitted with a large open star tip and pipe the mixture into the skins, dividing evenly and using all the mixture so that each skin is mounded with filling. Alternatively, spoon the potato mixture into the skins and smooth the tops.
- Lightly dust the top of each potato with paprika, then transfer to the oven and bake until the surfaces are lightly browned in spots, 15 to 20 minutes. Transfer to a platter and serve.
Do ahead: The potato skins can be filled up to 1 day ahead. Cover and refrigerate, then bring to room temperature before topping with paprika and baking again. They will take a few minutes longer to heat through and brown in the oven.
Garlicky Mashed Potato Cake
If you like the creaminess of mashed potatoes but not the uniform texture, try this potato cake, which is like a cross between hash browns and a classic mash. Made with fluffy baked russet potatoes and flavored with garlic, browned butter and tangy sour cream, the cake is cooked on the stovetop, then transferred to the oven, where it takes on a crispy, golden brown crust. Make sure your nonstick skillet is oven-safe, or use a very well-seasoned cast-iron skillet.
Total time: 2 hours, 15 minutes
- 3 pounds russet potatoes (about 6 medium-large), scrubbed
- 6 tablespoons unsalted butter
- 6 garlic cloves, smashed and peeled
- Kosher salt and freshly ground black pepper
- Pinch of ground nutmeg
- ½ cup crème fraîche or sour cream, at room temperature
- 1 tablespoon finely chopped chives
- Arrange an oven rack in the center position and heat the oven to 425 degrees. Bake the potatoes directly on the oven rack until the flesh is soft and tender and the skins are crispy, 60-75 minutes. Remove the potatoes from the oven and let them sit at room temperature just until they are cool enough to handle (they should still be hot). Lower the oven temperature to 400 degrees.
- Meanwhile, heat a 10-inch nonstick, oven-safe skillet over medium. Add the butter and swirl the skillet until the butter is melted and foamy, then add the garlic and cook, stirring occasionally, until both the garlic and butter are golden brown, about 3 minutes. Remove the skillet from the heat and set aside.
- Cut the still-hot potatoes in half and scoop the flesh out onto a cutting board (save the skins for snacking or discard). Use a knife or bench scraper to chop up the flesh so you have pieces of various sizes but none larger than a walnut half.
- Add the potato flesh to the skillet, season generously with salt and pepper and add a pinch of nutmeg. Add the crème fraîche or sour cream, and fold the mixture gently until the potatoes are evenly coated, then flatten it gently into a single layer. Place the skillet over medium-high heat and cook undisturbed until all the moisture has evaporated and the potatoes are starting to turn golden on the bottom, 5 to 8 minutes.
- Gently shake the skillet to loosen the potato cake, then transfer it to the oven and bake until the potatoes are lightly browned across the surface, 30 to 35 minutes. Remove the skillet and let sit for 10 minutes, then carefully invert the potato cake onto a serving platter (if making ahead, see note below). Top with chives and serve.
Do ahead: The potato cake can be made several hours in advance. Leave it in the skillet and set aside at room temperature, then reheat in the oven at 425 degrees for 10 to 15 minutes before serving.